I would honestly devote myself to serious research for at least several months first and ensure I had everything I needed. But if I did consider giving it a go, how do you think these two blue-eyed green monsters would do?

It's not that you can't breed rosetails. But since you are just beginning to breed, its best to avoid them for now because they carry deformed genes which could destroy your line. And once it gets into your line it will be hard to totally clean it out. Perhaps later, when you get the hang of it all.

What ever goal or plan is personal preference/availability, but are important to set before breeding. Just remember to be responsible and most important HAVE FUN.

What I would actually like to do with these two, if possible, is primarily try to get blue-eyed monsters. I would prefer to focus on that rather than on a particular color or tail type.

Well, happily, bettas don't suffer much from inbreeding till you're several generations in. So if you were to take the very best of this spawn, and breed the ones most like the male back to him, and the ones most like the female back to her, you could get two lines going (and a good percentage of blue-eyed monsters) and then be able to cross the lines back together.

;) look for a complimentary blue-eyed monster every 3rd generation and you're on your way!